Adding Case Resolution status

One of the common question or thing that people get missed is that how to add more “resolution status for Case (incident)” or more “Lost Reason on Opportunity (opportunity)” Record.
We look at the example steps for case record and all other entities status list can be changed similarly.
Step 1: Go to Settings – > Customization – > Customizable Settings -> Open Case Form
Step 2: Go to attributes -> Open statuscode attribute
Step 3: Select relevant state and then add relevant status reason in this drop down list
Step 4: save the changes and publish the entity.